Convertible plungers and methods for assembling the same in a medical barrel

Patent metadata

Field	Value
Publication number	US-10918800-B2
Application number	US-201716306536-A
Country	US
Kind code	B2
Filing date	Jan 13, 2017
Priority date	May 31, 2016
Publication date	Feb 16, 2021
Grant date	Feb 16, 2021

Abstract

Disclosed are plunger assemblies including various convertible plungers and methods of making the same. Each plunger assembly is configured for disposition within a barrel of a medical container, e.g., a syringe, and displaced within the barrel from an engagement position to a release position. The engagement position is configured to provide a compression seal between a storage sealing section of the plunger and an inner wall of the syringe barrel. In the release position, the compression seal is reduced or eliminated. Also disclosed are methods for making convertible plungers and assembling them into syringes, e.g., pre-filled syringes.

First claim

What is claimed is:

1. A convertible plunger for disposition within a barrel of a medical container, the barrel being configured for receipt of an injectable product therein and having a central axis and an interior wall surrounding the axis, the plunger being configured to be moved within the barrel along the axis from a storage mode to a dispensing mode, the plunger comprising:
a. a ring carrier having a compressible and resilient storage ring disposed thereon, the storage ring being configured for axial displacement along the ring carrier, the ring carrier comprising:
i. an annular storage platform that is comparatively more rigid than the storage ring, the storage ring being in an expanded state corresponding to an engagement position when the storage ring is disposed about the storage platform, wherein a storage sealing section of the storage ring is configured to apply outward radial pressure on the interior wall of the barrel;
ii. an annular dispensing platform having a narrower cross-sectional width or diameter than that of the storage platform, the storage ring being in a constricted state corresponding to a release position when the storage ring is disposed about the dispensing platform, wherein the storage sealing section is configured to provide less radial pressure on the interior wall than when in the engagement position or to provide no outward radial pressure on the interior wall; and
iii. an annular insertion platform, the insertion platform having a smaller maximum diameter or cross-sectional width than that of the storage platform, the storage ring being in a load position when the storage ring is disposed about the insertion platform so as to facilitate insertion of the ring carrier and storage ring into the barrel, wherein the storage sealing section is configured to provide less radial pressure on the interior wall than when in the engagement position or to provide no outward radial pressure on the interior wall, the storage ring being configured to move along the ring carrier between the load position, the engagement position and the release position; and

b. a plunger head mounted at a distal end of the plunger, the plunger head having a liquid sealing section configured to contact and provide a seal against the interior wall, wherein the plunger head is a separate component assembled with the ring carrier to form the convertible plunger.

2. The convertible plunger of claim 1 , the liquid sealing section having a film or a cap covering a product-facing surface and sidewall of the liquid sealing section, the film or cap comprising a fluoropolymer.

3. The convertible plunger of claim 1 , wherein the storage sealing section includes a plurality of annular ribs separated by an annular valley between ribs.

4. The convertible plunger of claim 3 , wherein the storage ring includes:
a. a storage sealing section having three outer annular ribs separated by annular valleys therebetween; and
b. a single inner rib on an inner diameter of the ring.

5. The convertible plunger of claim 4 , wherein the ring carrier comprises a transition region connecting the storage platform to the dispensing platform, the dispensing platform and transition region together providing a uniform annular inner radius about the ring carrier, the uniform annular inner radius comprising complementary mating geometry with the single inner rib to securely retain the storage ring about the dispensing platform when the storage ring is in the release position.

6. The convertible plunger of claim 1 , wherein the liquid sealing section comprises a thermoset rubber.

7. The convertible plunger of claim 1 , further comprising a connector body, the connector body having a distal end and a proximal end, the distal end of the connector body being secured to the plunger head, the proximal end of the connector body being secured to a distal end of the ring carrier.

8. The convertible plunger of claim 2 , the liquid sealing section having a film wrapped around a product-facing surface and sidewall of the liquid sealing section, the film comprising a fluoropolymer, wherein the film continues along an underside of the plunger head and is sandwiched between the plunger head and the connector body.

9. The convertible plunger of claim 1 , wherein the insertion platform is distal to the storage platform and the storage platform is distal to the dispensing platform.

10. A pre-filled syringe comprising:
a. a medical barrel having an inner wall and an injectable product, disposed in a product containing area of the medical barrel, the medical barrel having a distal dispensing end for dispensing the injectable product and an open proximal end configured for receipt of a convertible plunger; and
b. a convertible plunger disposed within the medical barrel, the plunger being movable within the barrel along the axis from a storage mode to a dispensing mode, the plunger comprising:
i. a ring carrier having a compressible and resilient storage ring disposed thereon, the storage ring being configured for axial displacement along the ring carrier, the ring carrier comprising:
aa. an annular storage platform that is comparatively more rigid than the storage ring, the storage ring being in an expanded state corresponding to an engagement position when the storage ring is disposed about the storage platform, wherein a storage sealing section of the storage ring applies outward radial pressure on the interior wall of the barrel;
bb. an annular dispensing platform having a narrower cross-sectional width or diameter than that of the storage platform, the storage ring being in a constricted state corresponding to a release position when the storage ring is disposed about the dispensing platform, wherein the storage sealing section provides less radial pressure on the interior wall than when in the engagement position or provides no outward radial pressure on the interior wall; and
cc. an annular insertion platform, the insertion platform having a smaller maximum diameter or cross-sectional width than that of the storage platform, the storage ring being in a load position when the storage ring is disposed about the insertion platform so as to facilitate insertion of the ring carrier and storage ring into the medical barrel, wherein the storage sealing section provides less radial pressure on the interior wall than when in the engagement position or provides no outward radial pressure on the interior wall, the storage ring being movable along the ring carrier between the load position, the engagement position and the release position; and

ii. a plunger head provided at a distal end of the plunger, the plunger head having a liquid sealing section configured to contact and provide a seal against the interior wall.

11. The pre-filled syringe of claim 10 , the storage sealing section in the constricted state:
a. having a reduced maximum diameter or cross-sectional width than the storage sealing section in the expanded state; and/or
b. being less resistant to inward radial compression compared to the storage sealing section in the expanded state.

12. The pre-filled syringe of claim 11 , the storage ring configured to be set in the expanded state through application of a setting force onto the convertible plunger in a distal direction, wherein subsequent application of an actuation force onto the convertible plunger in a distal direction reduces the expanded state of the storage ring to the constricted state to transition the plunger from storage mode to dispensing mode.

13. The pre-filled syringe of claim 10 , further comprising a connector body, the connector body having a distal end and a proximal end, the dist

Assignees

• Sio2 Medical Products Inc

Inventors

• Lilly Brian Russell
• Kelly Kenneth Wade
• Rogers Joseph W
• Giraud Jean-Pierre
• Rabinne Bruce
• Pichot Herve
• Hunt Benjamin
• Freeman Zachary Dean
• Roe Dalton
• Abrams Robert S

Classifications

• A61M2005/3121

  via the proximal end of a syringe, i.e. syringe end opposite to needle cannula mounting end · CPC title

• A61F9/0008

  Introducing ophthalmic products into the ocular cavity or retaining products therein (putting in contact lenses A61F9/0061; introducing or retaining media in cavities of the body in general A61M31/00) · CPC title

• A61M5/31513 Primary

  Piston constructions to improve sealing or sliding · CPC title

• A61M2207/00

  Methods of manufacture, assembly or production · CPC title

• A61M2005/3101

  Leak prevention means for proximal end of syringes, i.e. syringe end opposite to needle mounting end · CPC title